Devices for transferring power between rotating components and reciprocating components are used in various applications, especially piston type gas compressors and internal combustion engines. Many variations have been designed, with varying levels of success. The most common central element is usually a crank or a cam. The present invention represents an improvement in a cam type device, especially wherein the cam has an odd number of lobes.
A major problem which has been encountered with prior cam type devices is the effective return of the reciprocating element back toward the cam during negative cam pressure, after the reciprocating element has passed the top of a lobe. Various mechanisms have been devised to resolve this problem, but many are complicated, cumbersome, mechanically weak, cause loss of efficiency and/or costly.
Some engine mechanisms solve the above stated problem by using a double-acting reciprocating element with diametrically opposed pistons rigidly fixed at either end thereof, each piston having a roller follower in contact with the cam. The firing of one piston causes the return of the other piston. However, unless the cam has a constant diameter, the roller follower of the returning piston will briefly separate from the cam, causing what is known as "piston slap" an undesirable event for a device which is subject to any significant load. Moreover, a small amount of wear even in a constant diameter cam can cause looseness which results in the same event. A means is needed for maintaining contact of opposing roller followers with the cam, and take up any slack due to wear.
Some engine designs use springs between the roller followers and pistons. Such an arrangement is considered impractical because of power loss caused by the spring absorbing energy from the piston as it is transferred to the roller follower. Other engines have springs located in both opposing pistons where complete disassembly of the engine is necessary for spring adjustment and heat is intense.
Listed herein below for further information are U. S. Patents which show examples of various transfer mechanisms:
1. U.S. Pat. No. 717,445, issued to O. B. Nestius on Dec. 30, 1902. PA1 2. U.S. Pat. No. 871,707 issued to E. Koch on Nov. 19, 1907. PA1 3. U.S. Pat. No. 1,309,257, issued to L. A. Martins on Jul. 8, 1919. PA1 4. U.S. Pat. No. 1,355,451, issued to L. R. Carpenter on Oct. 12, 1920. PA1 5. U.S. Pat. No. 1,445,474, issued to L. E. Benson et.al. on Feb. 13, 1923. PA1 6. U.S. Pat. No. 1,594,045, issued to H. Caminez on Jul. 27, 1926. PA1 7. U.S. Pat. No. 1,765,237, issued to F. H. King on Jun. 17, 1930. PA1 8. U.S. Pat. No. 1,774,087, issued to William G. Dunn on Aug. 26, 1930. PA1 9. U.S. Pat. No. 1,792,062, issued to O. G. Barnum on Feb. 10, 1931. PA1 10. U.S. Pat. No. 1,810,688, issued to C. A. Toce et.al. on Jun. 16, 1931. PA1 11. U.S. Pat. No. 1,830,046, issued to F. White on Nov. 3, 1931. PA1 12. U.S. Pat. No. 1,863,877, issued to A. L. Rightenour on Jun. 21, 1932. PA1 13. U.S. Pat. No. 1,931,401, issued to B. L. Baisden on Oct. 17, 1933. PA1 14. U.S. Pat. No. 1,965,548, issued to A. L. Hart on Jul. 3, 1934. PA1 15. U.S. Pat. No. 2,120,657, issued to H. R. Tucker on Jun. 14, 1938. PA1 16. U.S. Pat. No. 2,124,604, issued to W. B. Bidwell on Jul. 26, 1938. PA1 17. U.S. Pat. No. 3,572,209, issued to H. F. Aldridge et.al. on Mar. 23, 1971. PA1 18. U.S. Pat. No. 3,584,610, issued to Kilburn I. Porter on Jun. 15, 1971. PA1 19. U.S. Pat. No. 3,604,402, issued to Ernst Hatz on Sep. 14, 1971. PA1 20. U.S. Pat. No. 4,331,108, issued to Brian S. Collins in May 25, 1982. PA1 21. U.S. Pat. No. 4,493,296, issued to Gerald J. Williams on Jan. 15, 1985. PA1 22. U.S. Pat. No. 4,545,336, issued to William M. Waide on Oct. 8, 1985. PA1 23. U.S. Pat. No. 4,697,552, issued to Nikola T. Kolev on Oct. 6, 1987.